Pedal-crank extension attachment.



No. 628,l73., Patented July 4, l899.--

J. B. YOUNG. PEDAL CRANK EXTENSION ATTACHMENT.

, filo" Modal.)

UNITED STATES PATENT OFFICE.

, JOHN B. YOUNG, OF CHICAGO, ILLINOIS.

PEDAL-CRANK EXTENSION ATTACHM ENT.

SPECIFICATION forming part of Letters Patent No. 628,173, dated July 4,1899. Application filed May 16,1898. S ria1N 680,845. (N0 model.)

To aZZ whom it may concern.-

' Be it known that I, JOHN B. YOUNG, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a new and useful Improvement in Pedal-Crank ExtensionAttachments, of which the following is a specification.

My invention relates to a pedal-crank extension attachment which may beemployed in connection with the pedal-cranks and pedals of commonconstruction for the purpose of securing an increased leverage wheresuch increased leverage is desired.

My object is to provide an extension attachment for crank-arms which maybe cheaplymanufactured and readily applied to cranks now in common use,thereby rendering it possible for the wheelman at small expense toconvert his wheel into one with extensible cranks. When it is notdesired to use the increased leverage, the extension attachments may bequickly removed, and the cranks are then left in their ordinaryform,with no attachment or securing parts whatever to encumber them.Thus the rider may, when the roads and wind are favorable, make a longrun us ing the cranks without the extensions, but in making the returntrip the wind may be against the-rider or the roads in poor condition,when the extensions may be slipped upon the cranks and used to thegreatest advantage.

In the accompanying drawings, Figure 1 is a View of an ordinarypedal-crank equipped with my improved extension attachment, the outerside of the crank being toward the left I side of the sheet; Fig. 2, asimilar view of the outer side of the crank Fig. 3, a broken sectionalview taken on line 3 of Fig. 2, a fragment of a pedal being shown inplace attached to the extension; Fig. 4, an inner face view of theextension attachment, and Fig. 5 an outer face view of the same.

A is the pedal-crank, provided at its inner end with acrankshaft-receiving perforated head A and at its outer end with apedal-pinreceiving perforated head A B is the extension attachment,comprising, preferably,a portion B,provided with a crankhead-receivingcircular depression 3 and a screw-bolt-receiving perforation s, apedalbearing head B provided with a pedal-pinreceiving perforation r,and a shank B provided with a rectangular opening 19 and at its extremeend with a curved bridge-piece p. The shank B is preferably offsetsomewhat from the portion B, as shown in Fig. 1, so'that thebridge-piece p bears on the side of the crank-arm opposite to the faceof the crankhead A which bears against the depressed circular surface 5.

To apply the attachment to a pedal-crank, the pedal is first removedfrom the head of the crank, and the crank-head is then inserted throughthe rectangular perforation p of the shank B from the side of theattachment opposite to that shown in Fig. 4. The crank is then given aquarter-turn and brought into substantial alinement with theextension,with the head of the crank fitting into the circular recessand the crank-arm itself fitting into the concave surface of thebridgepiece p. The extension is secured in place by means of ascrew-bolt or threaded stud C of the same diameter and thread pitch asthe shank of the pedal-pin and of sufficient length to extend throughthe perforation s and screw into the outer crank-head. The pedal-pin Dof the pedal D is then screwed into the perforation r of thepedal-bearing extension B and the transformation is complete.

It will be observed that the only portion of the attachment whichprojects inward beyond the surface of the crank-arm is the comparativelythin bridge-piece p. Inasmuch as the clearing-space between thecrank-arm andframe is small the peculiar manner of attachin g theextension to the crank-arm is of great advantage in this connection, aswell as for its simplicity and the readiness with which it is attachedto the crank-arm itself.

Minor changes in details may be made without departing from the spiritof my invention, the essential feature of which consists in thelever-like connection between the attachment and the crank-arm-that' isto say, I regard as within the spirit of myinvention an attachmentprovided with a crank-head-receiving portion, a pedal-bearing head, anda shank provided with means for engaging the crankarm. I

What I claim as new, and desire to secure by Letters Patent, is

1. Acrank-arm extension attachment,comprising a recessedcrank-head-receiving portion, a pedal-bearing perforated head carriedthereby,a shank extending from the crank: head-receiving portion, andmeans on said shank for engaging the crank-arm and fixing the extensionrigidly to the crank-arm, substantially as and for the purpose setforth.

2. A crank-arm extension attaehn1ent,colnprising a recessedcrauk-head-receiving portion, a pedal-bearing perforated head carriedthereby, and a shank extending from the crank-head-receiving portionprovided with a rectangular-shaped perforation and below saidperforation and at the inner side of the shank with a curvedbridge-piece, substantially as and for the purpose set forth.

3. The combination with a pedal-crank supplied at its outer end with athreaded perforation, of an extensionattachment for the crank-armprovided at its outer end with a threaded perforation of like diameterand pitch,a pedal supplied with a pedal-pin having a threaded shankadapted to fit either of said perforations, a perforated recessedportion on the attachment for receiving the outer crankhead, ascrew-bolt. of sufficient length and diameter to extend through saidrecessed portion and screw into the threaded crank-head to secure theattachment to the crank when its use is desired, and means acting withsaid bolt connection to render said extension rigid with relation to thecrank, substantially as described.

4. The combination of a pedal-crank supplied at its outer end with athreaded perforation, an extension attachment for the crank-arm providedat its outer end with a threaded perforation of like diameter andpitch,a-pedal supplied with apedal-pin having a threaded shank adaptedto fit either of said perforations, a perforated recessed portion on theattachment for receiving the outer face of the outer crank-head, a shankon the attachment provided with crank-arm-engaging means, and ascrew-bolt of sufficient length ,and diameter to extend through saidrecessed portion and screw into the threaded crankhead to secure theattachment to the crank when its use is desired, substantially asdescribed.

5. The combination with a pedal-crank supplied at its outer end with athreaded perforation, of an extension attachment for the crank-armprovided at its free end with a threaded perforation of like diameterand pit(-h,a pedal supplied with a pedalepin having a threaded shankadapted to fit either of said perforations, and a threaded stud of thesame diameter and thread pitch as the pedal-pin shank serving to securethe extension to the crank, substantially as and for the purpose setforth.

JOHN B. YOUNG.

In presence of- J. H. LEE, DAN. W. LEE.

